检索结果-南通市图书馆

Chinese journal of Structural Chemistry 2003年第1期22卷 50-54页

作者： WAngRui－hu ChenLi－hua 等 StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatteTheCineseAcademyofSciencesFuzhouFujian350002China jianouInstituteofEnvironmentsupervisi

The assembly of 1,4-benzenedicarboxylic acid (H2bdc), 4,4?bipyridine (4,4?bipy), trimethyltin chloride and MnBr24H2O in hydrothermal conditions gave rise to a hydrogen-bonded three-dimensional complex {[Mn(4,4?bipy)4H2O](bdc)}n which has been characterized by single- crystal X-ray diffraction. The complex crystallizes in the monoclinic system, space group P2/n with a = 7.0001(2), b = 11.5540(3), c = 11.4192(1) ? = 101.754(2)? V = 904.21(4) 3, Z = 2, C18H20MnN2O8, Mr = 447.30, Dc = 1.643 g/cm3, F(000) = 462 and m(MoK? = 0.783 mm-1. The final R and wR are 0.0499 and 0.1301, respectively for 1335 observed reflections with I ≥ 2(I). The Mn (Ⅱ) is six-coordinated in a distorted octahedral geometry. 4,4?Bipyridine in a m-bridge mode links [Mn(H2O)4]2+ into a linear cation chain. bdc acts as a counter anion and links the linear chains into a three-dimensional structure through hydrogen bonds.

关键词： manganese (Ⅱ) complex crystal structure synthesis hydrogen bonds

Thermal effect of thermokarst lake on the permafrost under embankment

在线全文

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2021年第1期12卷 76-82页

作者： PEng Er-Xing SHEng Yu hu Xiao-Ying WU ji-Chun CAO Wei State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China School of Civil Engineering Lanzhou University of TechnologyLanzhou730050China

In permafrost regions of the Qinghai-Tibet Plateau,road disaster caused by permafrost degradation cannot be *** a common thermal disaster in permafrost regions,thermokarst lake has serious thermal erosion on permafrost and results in permafrost degradation *** study focused on two subgrade cross-sections of Gonghe-Yushu Highway in the Qinghai-Tibet Plateau to analyze thermal effect of thermokarst lake on the permafrost under *** analysis infers that thermokarst lake can transfer heat to permafrost under the embankment,as a heat resource,and the heat flux decreases with the distance away from thermokarst lake in horizontal and vertical *** lake can cause average ground temperature of permafrost under the embankment increasing,and with less distance from the thermokarst lake the temperature increases more *** lake results in 14 m thickness melting interlayer in soil under lake and change shape of melting area.

关键词： Thermokarst lake Permafrost Ground temperature Heat budget

Mechanical properties and frictional resistance of Al composites reinforced with Ti3C2Tx MXene

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2020年第4期31卷 996-999页

作者： jie hu Shibo Li j.ng Zhang Qiuying Chang Wenbo Yu Yang Zhou School of Mechanical and Electronic Control Engineering Beijing Jiaotong UniversityBeijing 100044China

Two-dimensional(2D)Ti3C2Tx MXene is an attractive additive not only used in base oil due to its low friction coefficient,but also used in composites due to its high aspect ratio and rich surface functional *** far there has been intense research into polymer matrix composites reinforced with Ti3C2Tx,Here we report on the use of 2D Ti3C2Tx to enhance the mechanical and frictional properties of Al matrix ***3C2Tx/Al composites were designed and prepared by pre s sureless sintering followed by hot extrusion *** prepared composites exhibit a homogeneous distribution of *** Vickers hardness and the tensile strength continuously increase with increasing Ti3C2Tx content.A hardness of 0.52 GPa and a tensile strength of 148 MPa were achieved in the 3 wt%Ti3C2Tx/Al *** frictional properties of pure Al and the Ti3C2Tx/Al composite were comparably studied under dry sliding.A low friction coefficient of 0.2,twice lower than that of pure Al,was achieved in the 3 wt%Ti3C2Tx/Al ***3C2Tx acting as a solid lubricant reduces the abrasive wear in the composite,improving the frictional properties of Al matrix composites.

关键词： Ti3C2Tx Mxene Al composites Microstructure Mechanical properties Frictional properties

Producing Designer Oils in Industrial Microalgae by Rational Modulation of Co-evolving Type-2 Diacylglycerol Acyltransferases

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2017年第12期10卷 1523-1539页

作者： Yi Xin Yandu Lu Yi-Ying Lee Li Wei j.ng jia Qintao Wang Dongmei Wang Fali Bai Hanhua hu Qiang hu jin Liu Yantao Li jian Xu Single-Cell Center CAS Key Laboratory of Biofuels and Shandong Laboratory of Energy Genetics Qingdao Institute of BioEnergy and Bioprocess TechnologyChinese Academy of Sciences Qingdao Shandong 266101 China Institute of Marine and Environmental Technology University of Maryland Center for Environmental Science and University of Maryland Baltimore CountyBaltimore MD 21202 USA Institute for Food and Bioresource Engineering and Department of Energy and Resource Engineering College of Engineering Peking University Beijing 100871China Center for Microalgal Biotechnology and Biofuels Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China Diatom Biology Group Institute of Hydrobiology Chinese Academy of Sciences Wuhan Hubei 430072 China Core Laboratory Qingdao Institute of BioEnergy and Bioprocess Technology Chinese Academy of Sciences Qingdao Shandong 266101 China University of Chinese Academy of Sciences Beijing 100049 China These authors contributed equally to this article.

Microalgal oils, depending on their degree of unsaturation, can be utilized as either nutritional supplements or fuels; thus, a feedstock with genetically designed and tunable degree of unsaturation is desirable to maximize process efficiency and product versatility. Systematic profiling of ex vivo （in yeast）, in vitro, and in vivo activities of type-2 diacylglycerol acyltransferases in Nannochloropsis oceanica （NoDGAT2s or NoDGTTs）, via reverse genetics, revealed that NoDGAT2A prefers saturated fatty acids （SFAs）, NoDGAT2D prefers monounsaturated fatty acids （MUFAs）, and NoDGAT2C exhibits the strongest activity toward polyunsaturated fatty acids （PUFAs）. As NoDGAT2A, 2C, and 2D originated from the green alga, red alga, and eukaryotic host ancestral participants of secondary endosymbiosis, respectively, a mecha- nistic model of oleaginousness was unveiled, in which the indigenous and adopted NoDGAT2s formulated functional complementarity and specific transcript abundance ratio that underlie a rigid SFA：MUFA：PUFA hierarchy in triacylglycerol （TAG）. By rationally modulating the ratio of NoDGAT2A＇：2C^D transcripts, a bank of N. oceanica strains optimized for nutritional supplement or fuel production with a wide range of degree of unsaturation were created, in which proportion of SFAs, MUFAs, and PUFAs in TAG varied by 1.3-, 3.7-, and 11.2-fold, respectively. This established a novel strategy to simultaneously improve productivity and quality of oils from industrial microalgae.

关键词： biofuels degree of unsaturation genetic engineering diacylglycerol acyltransferase Nannochloropsis

2021-2023年河南省某医院产碳青霉烯酶大肠埃希菌的分子流行特征分析

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中华预防医学杂志 2025年第1期59卷 53-61页

作者：胡玥刘心伟任彦颖刘冬梅刘玉春夏晴李永伟王春霞河南省中医院检验中心河南省防治耐药菌感染中医药重点实验室郑州450002 河南中医药大学第二临床医学院郑州450046 河南省中医院生殖医学科郑州450002

目的对2021—2023年河南省某医院产碳青霉烯酶大肠埃希菌(Carbapenemase-prodcing Escherichia coli,CPECO)的耐药基因流行特征进行分析,为控制CPECO的院内传播感染提供数据支撑和理论依据。方法采用横断面研究,对2021—2023年河南省中... 详细信息

目的对2021—2023年河南省某医院产碳青霉烯酶大肠埃希菌(Carbapenemase-prodcing Escherichia coli,CPECO)的耐药基因流行特征进行分析,为控制CPECO的院内传播感染提供数据支撑和理论依据。方法采用横断面研究,对2021—2023年河南省中医院临床微生物实验室经VITEK-2 Compact鉴定和药敏试验确认的30株碳青霉烯耐药的大肠埃希菌(CRECO),使用碳青霉烯酶抑制剂增强试验进行碳青霉烯酶初筛,胶体金免疫层析法和聚合酶链反应(PCR)法分别对常见碳青霉烯酶表型和基因型(bla_(KPC)、bla_(NDM)、bla_(VIM)、bla_(IMP)、bla_(OXA))进行确证,同时使用PCR法对常见超广谱β-内酰胺酶(ESBL)基因型(bla_(SHV)、bla_(TEM)、bla CTX)予以确证;对碳青霉烯酶和ESBL阳性菌株的PCR扩增产物进行Sanger测序,测序产物在Blast网站中进行比对,确定确切的碳青霉烯酶和ESBL基因型;采用Achtman多位点序列分型方案对CPECO进行序列分型(ST),确定不同菌株之间的克隆关系。结果共筛选出CPECO 21株;药敏试验结果显示,CPECO菌株呈现泛耐药性,对单环类(氨曲南)和甲氧苄啶/磺胺甲噁唑的耐药率在60%以上(16/21、14/21),其余抗菌药物的耐药率为100%。仅对氨基糖苷类药物和磷霉素保持相对较高的敏感性,未发现对替加环素和多黏菌素耐药的菌株。胶体金免疫层析法检出bla_(NDM)型18株,bla_(KPC)型2株,bla_(IMP)型1株;耐药基因PCR产物测序分型bla_(NDM)-5型17株,bla_(NDM)-4型1株,bla_(KPC)-2型2株,bla_(IMP)-4型1株,与筛选试验和胶体金免疫层析法结果完全吻合。ESBL耐药基因检测显示,bla_(TEM)检出率为42.9%(9/21),bla CTX-M为33.3%(7/21),bla_(SHV)为4.8%(1/21),产bla_(NDM)型CPECO同时携带两种ESBL耐药基因的比率为27.8%(5/18);MLST分型结果发现11种ST型,包括1个ST155复合群和9个独立型,其中ST167型7株,ST410型5株,ST58、ST68、ST69、ST93、ST131、ST155、ST648、ST1114和ST3268各1株。结论本研究CPECO主要耐药机制为产bla_(NDM)-5型碳青霉烯酶,同时携带bla_(TEM)-1D型和(或)bla CTX-M-15型ESBL比例较高。MLST分型发现,CPECO的流行株呈现一定的多态性,但ST167和ST410存在多个克隆复合群的克隆性传播。

关键词：大肠埃希菌耐药基因多位点序列分析流行性

Impact of the carbon market on investment benefits of power-grid enterprises in China: a system dynamics analysis

在线全文

学校读者我要写书评

暂无评论

Global Energy Interconnection 2024年第4期7卷 402-414页

作者： Wanning Mao Liang hu Wenjuan Niu Xiaorong Sun Lili Hao Abimbola Susan Ajagun School of Public Administration Hohai University211100NanjingP.R.China Business School Hohai UniversityNanjing 211100P.R.China School of Electrical and Power Engineering Hohai UniversityNanjing211100P.R.China College of Electrical Engineering&Control Science Nanjing Tech UniversityNanjing 211816P.R.China School of Electrical Engineering and Technology Federal University of TechnologyMinnaNigeria

The power grid,as the hub connecting the power supply and consumption sides,plays an important role in achieving carbon neutrality in *** emerging carbon markets,assessing the investment benefits of power-grid enterprises is ***,studying the impact of the carbon market on the investment and operation of powergrid enterprises is key to ensuring their efficient ***,few studies have examined the interaction between the carbon and electricity markets using system dynamics models,highlighting a research gap in this *** study investigates the impact of the carbon market on the investment of power-grid enterprises using a novel evaluation system based on a system dynamics model that considers carbon-emissions from an established carbon-emission accounting ***,an index system for benefit evaluation was constructed from six aspects:financing ability,economic benefit,reliability,social responsibility,user satisfaction,and carbon-emissions.A system dynamics model was then developed to reflect the causal feedback relationship between the impact of the carbon market on the investment and operation of power-grid *** simulation results of a provincial power-grid enterprise analyze comprehensive investment evaluation benefits over a 10-year period and the impact of carbon emissions on the investment and operation of power-grid *** study provides guidelines for the benign development of power-grid enterprises within the context of the carbon market.

关键词： Carbon market Power-grid enterprises Investment benefit evaluation System dynamics analysis

Electrochemical synthesis ofα,α-dihaloacetophenones from terminal alkyne derivatives

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2020年第7期31卷 1855-1858页

作者： Zhibin Li Qi Sun Peng Qian Kangfei hu Zhenggen Zha Zhiyong Wang Hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Soft Matter Chemistry&Center for Excellence in Molecular Synthesis of Chinese Academy of SciencesCollaborative Innovation Center of Suzhou Nano Science and Technology&School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China

By virtue of electrochemistry,a series ofα,α-dihaloacetophenones were easily obtained with good to excellent *** electrochemical procedure was taken in a divided cell with constant current in aqueous *** reaction can be carried out smoothly at room temperature under metal and oxidant free condition,which provides an eco-friendly synthesis for theα,α-dihaloacetophenone derivatives.

关键词： Electrochemistry Alkyne derivatives α,α-Dihaloacetophenones Divided cell Oxidant free

Evidence of aircraft activity impact on local air quality: A study in the context of uncommon airport operation

在线全文

学校读者我要写书评

暂无评论

journal of Environmental Sciences 2023年第3期125卷 603-615页

作者： Hao Xu Kai Xiao jun Pan Qingyan Fu Xiaodong Wei junrui Zhou Yamei Yu Xue hu huarui Ren jinping Cheng Shitao Peng Ningning Hong Yin Ye Ning Su Zehui He Tao hu School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Wuhan Environmental Protection Science Academy Wuhan 430015China Shanghai Environmental Monitoring Center Shanghai 200233China jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China East China Air Traffic Management Bureau CAAC Shanghai 200335China China-UK Low Carbon College Shanghai 201306China Tianjin Research Institute for Water Transport Engineering Ministry of TransportTianjin 300456China

Wuhan Tianhe International Airport (WUH) was suspended to contain the spread of COVID-19,while Shanghai Hongqiao International Airport (SHA) saw a tremendousflight *** of a major international airport is extremely rare and thus represents a unique opportunity to straightforwardly observe the impact of airport emissions on local air *** this study,a series of statistical tools were applied to analyze the variations in air pollutant levels in the vicinity of WUH and *** results of bivariate polar plots show that airport SHA and WUH are a major source of nitrogen ***,NO_(2)and NO diminished by 55.8%,44.1%,76.9%,and 40.4%,33.3% and 59.4% during the COVID-19 lockdown compared to those in the same period of 2018 and 2019,under a reduction in aircraft activities by 58.6%and61.4%.The concentration of NO_(2),SO_(2)and PM_(2.5)decreased by 77.3%,8.2%,29.5%,right after the closure of airport WUH on 23 january *** average concentrations of NO,NO_(2)and NOxscatter plots at downwind of SHA after the lockdown were 78.0%,47.9%,57.4%and 62.3%,34.8%,41.8%lower than those during the same period in 2018 and ***,a significant increase in O_(3)levels by 50.0% and 25.9%at WUH and SHA was observed,*** results evidently show decreased nitrogen oxides concentrations in the airport vicinity due to reduced aircraft activities,while amplified O_(3)pollution due to a lower titration by NO under strong reduction in NOxemissions.

关键词： Aircraft emissions COVID-19 Nitrogen oxides Ozone Airport closure

君子有三畏:大学生君子人格的异质性及其与敬畏感的网络关系

在线全文

学校读者我要写书评

暂无评论

心理科学 2025年第1期48卷 107-117页

作者：林荣茂胡添祥叶玉珊郑婉卿余巧华谢涵颖连榕福建师范大学心理学院福州350117

中华优秀传统文化孕育的君子人格对新时代培育积极社会心态具有重要意义。本研究采用整群抽样法,以1235名大学生为对象进行问卷调查,探讨君子人格的异质性及其与敬畏感的网络关系。研究结果表明,大学生君子人格存在异质性,可以分为狷者(... 详细信息

中华优秀传统文化孕育的君子人格对新时代培育积极社会心态具有重要意义。本研究采用整群抽样法,以1235名大学生为对象进行问卷调查,探讨君子人格的异质性及其与敬畏感的网络关系。研究结果表明,大学生君子人格存在异质性,可以分为狷者(32.52%)、中行者(56.92%)和狂者(10.56%);不同亚组大学生的敬畏感存在显著差异,以狂者最高;三个亚组的核心节点均为生命敬畏感、道德敬畏感、自然敬畏感和恭而有礼,但在狂者中,恭而有礼的预期影响更大,生命敬畏感、道德敬畏感和自然敬畏感的预期影响更小,恭而有礼与智仁勇的正向关联性、有所不为与关系敬畏感的负向关联性更强。本研究对新时代大学生理想人格塑造和敬畏感培育具有一定的启示,彰显了文化自信。

关键词：君子人格敬畏感潜在剖面分析网络分析回归混合模型

3D-Flair MRI和前庭功能在极重度突发性聋患者预后评估中的应用

在线全文

学校读者我要写书评

暂无评论

中华耳鼻咽喉头颈外科杂志 2025年第1期60卷 2-9页

作者：戴清蕾熊文萍王英俊胡娜孙晓樊兆民王海波王明明山东大学山东省耳鼻喉医院耳内科济南250022 山东大学山东省耳鼻喉医院医学影像中心济南250022 山东大学山东省耳鼻喉医院耳科中心济南250022

目的分析极重度突发性聋患者的内耳三维液体衰减反转恢复(three dimensional fluid attenuated inversion recovery,3D-Flair)MRI表现、前庭功能情况及其与预后的相关性,探讨突发性聋可能的预后评估指标。方法回顾性分析2018年3月至2020... 详细信息

目的分析极重度突发性聋患者的内耳三维液体衰减反转恢复(three dimensional fluid attenuated inversion recovery,3D-Flair)MRI表现、前庭功能情况及其与预后的相关性,探讨突发性聋可能的预后评估指标。方法回顾性分析2018年3月至2020年8月山东省耳鼻喉医院耳内科住院的成人单侧极重度突发性聋患者的临床资料。根据患者内耳3D-Flair MRI的结果分为MRI正常组和异常组,异常组又分为内耳高信号未吸收、高信号吸收和血迷路屏障破坏三组。应用SPSS 26.0统计软件分析各组患者听力疗效、冷热实验、前庭诱发肌源性电位(VEMP)、视频头脉冲试验(vHIT)以及头晕/眩晕伴发率的差异。结果共收集资料完整患者191例(男97例,女94例,年龄13~69岁),其中内耳3D-Flair MRI正常组50例,异常组共141例(包括内耳高信号未吸收组50例,内耳高信号吸收组71例,血迷路屏障破坏组20例)。四组间年龄、性别、耳聋侧别和病程差异均无统计学意义(P值均>0.05)。治疗后听力疗效比较,内耳3D-Flair MRI正常组的显效率和总有效率均高于异常组,差异具有统计学意义(P值均<0.05)。四组间比较,正常组和内耳高信号吸收组的显效率和总有效率差异具有统计学意义(χ^(2)=4.007,P=0.045;χ^(2)=6.925,P=0.009)。内耳3D-Flair MRI异常组的冷热试验、vHIT结果异常率及头晕/眩晕症状的发生率均高于正常组,差异具有统计学意义(P值均<0.05);MRI异常的三组间眼肌前庭诱发肌源性电位(oVEMP)异常率、vHIT异常率、伴头晕/眩晕发生率差异均有统计学意义(P值均<0.05);四组间冷热试验、oVEMP异常率、vHIT异常率、头晕/眩晕发生率差异均有统计学意义(P值均<0.05)。伴头晕/眩晕患者的冷热试验、颈肌前庭诱发肌源性电位(cVEMP)、vHIT阳性率,均高于不伴头晕/眩晕患者,差异具有统计学意义(P值均<0.05);伴头晕/眩晕患者的vHIT后半规管和水平半规管的异常率显著增高,与不伴头晕/眩晕患者相比差异具有统计学意义(P值均<0.05);不伴头晕/眩晕患者的痊愈率、有效率和总有效率均明显高于伴头晕/眩晕患者,差异具有统计学意义(P值均<0.05)。结论内耳3D-Flair MRI和前庭功能检查对极重度突发性聋患者的预后评估具有参考价值。内耳3D-Flair MRI异常,尤其是内耳高信号吸收者,前庭功能异常和头晕/眩晕伴发率高,预后差。伴头晕/眩晕症状极重度突发性聋患者更易出现前庭功能检查结果异常,其后半规管和水平半规管更易受累。

关键词：听觉丧失,突发性磁共振成像前庭功能试验眩晕头晕